tranvis suddenly yields an error on this command

the matplotlib bug seems to be fixed in 2.1.1

python 3.5 currently runs into a bug of matplotlib 2.1. May be removed
as this is updated on travis-ci.

add python 3.6

`pip install -e .` seems to copy files locally, such that the version
retrievel seems to break. `python setup.py install` should do eveything
important anyways.

add cython>=0.18 dep

travis container based infrastructure

remove --user in pip install

use miniconda2 to install dependencies

use before script section

Support for Particle Shape Orders 0 and 1.